In recent years, along with high frequency in semiconductor elements, a semiconductor package (a structure in which one semiconductor element is mounted on a substrate for package) and a composite module (a structure in which a plurality of semiconductor elements are mounted on a substrate for module) suitable for transmission of high-frequency signals have been developed. In related arts, a semiconductor package including a semiconductor element connected to a mounting substrate by wire bonding has mainly been used. However, according to such a semiconductor package, it is impossible to sufficiently achieve high frequency characteristic due to inductance components of a wire, and performance of the semiconductor package varies due to manufacturing variations of a wire length. Further, an active surface faces upward (face-up mounting) in the semiconductor element that is connected by wire bonding, which increases radiation noise. Accordingly, a method of covering the semiconductor element with a metal cap for an electromagnetic shield is employed in the semiconductor package in which a semiconductor element of high frequency is face-up mounted.
On the other hand, another semiconductor package is reported that uses a flip-chip connection (face-down mounting) in which a bump is formed in a connection pad of a semiconductor element and the semiconductor element is connected to a mounting substrate so that an active surface of the semiconductor element faces the mounting substrate. According to the flip-chip connection, the semiconductor element and the mounting substrate are connected in a short distance compared to face-up mounting by wire bonding, which can reduce transmission loss of signals. Further, manufacturing variations can be reduced and the device can be manufactured with low cost. Further, since the active surface of the semiconductor element faces the side of the mounting substrate, radiation noise can be made small by providing a ground electrode that is sufficiently wide on the mounting substrate (grounding measure). Another technique to cover a semiconductor element mounted on a mounting substrate with a conductor serving as an electromagnetic shield has been developed as a structure with no metal cap (e.g., see patent literatures 1 and 2).